The present invention relates to a display technique of data managed in a database management system.
As a typical technique for faster data aggregation processing in a multidimensional database management system, there is pre-aggregation. The pre-aggregation is a method of finishing aggregation calculation when reading data into a database and preserving the result (Pendse, N., and Creeth, R. F., *The OLAP Report*, pp. 69–77, Business Intelligence, 1995). Upon receiving an aggregation request, it is sufficient to only read out an aggregating value previously calculated.
However, it is known that the total amount of aggregate data obtained by aggregating multidimensional material data in various ways cause combinational burst with an increase of dimension or an increase of dimension hierarchy (the aforementioned paper). It becomes impossible in a large scale database to previously aggregate all considerable aggregate data.
In order to cope with this problem, there is proposed such a method of previously creating and storing only aggregating values of an aggregate pattern specified by the user (JP-A-8-329101). Because it is possible to reduce the total amount of stored aggregate data while increasing the speed of aggregation processing of an aggregate pattern requested by the user.
Here, the aggregate pattern is a combination of aggregation levels of respective dimensions. Furthermore, an aggregation level is a level to which a member corresponding to an aggregation value in the aggregation hierarchy of each dimension.
As an aggregate pattern specifying method of pre-aggregation of a conventional multidimensional database management system, a method of inputting an aggregation level of each dimension for each specified aggregate pattern is typical. For example, in an example shown in JP-A-8-329101, an aggregate pattern is made to be specified by using a table having a form shown in FIG. 32.
A table 3200 of FIG. 32 is a table for making a user specify index items used to create an aggregate data table. In a leftmost column, items which can be specified are displayed. A second column and subsequent columns correspond to aggregate tables to be created. Numerals of the top row of the table 3200 indicate identification numbers of aggregate data tables.
When specifying aggregate tables to be created, pertinent index items are selected. In a column corresponding to a table, “∘” is displayed on specified items. For example, in “02,” aggregate data of the sales are created in items of a branch office and a section. By using this method, aggregation processing of items requested by the user is previously conducted.